Rotatable valve having upper and lower parts

ABSTRACT

A valve apparatus, in particular a rotatable valve comprising an upper part (10) and a lower part (6) which are demountably attached to each other. The valve&#39;s lower part (6) is mainly U-formed with sealing surfaces (17,18) arranged on the outwardly facing side faces, which sealing surfaces, in the case of closed valve bear against at least one valve seat on the valve housing&#39;s inlet and/or outlet end, and upper part&#39;s (10) external face is designed for totally or partly supporting bearing against lower part&#39;s (6) internal face and comprising a passage (34) designed to accommodate equipment, for example controlling or metering instruments in the upper part (10) can, in the case of closed valve, be lifted out of the valve housing (1) for maintenance.

TECHNICAL FIELD

This invention concerns a device associated with a valve, in particulara rotatable valve comprising an upper part and a lower part which aredetachably joined to each other.

BACKGROUND ART

Valves of the kind mentioned above can be made sufficiently large androbust in order to be mounted onto pipelines which transporthydrocarbons, particularly subsea pipelines, but the invention can alsobe exploited in other environments and in smaller dimensions.

In the Norwegian patent application No. 860923, a ball valve isdisclosed which is intended for connection with a pipeline system whichconveys gas and/or oil at considerable sea depths. The valve can bedemounted in a submerged state for instance for inspection or repair.Replacement of the internal vital parts can take place without any kindof extra cover and without the fluid in the pipeline leaking out duringdemounting, or without water from the surrounding environment being ableto penetrate into the pipeline. This is achieved in that the rotatablemember of the known valve comprises an upper part and a lower part. Theupper part, which can be demounted from the valve housing, comprises,amongst other parts, the main packings of the valve. The lower partcontains two displaceable sleeves which, when the valve can be demountedfrom the valve housing, comprises, amongst other parts, the mainpackings and two displaceable sleeves which, when the valve is open, aredisplaced outwards to engage with bearings in the valve housing, therebyforming a leakproof, continuous fluid passageway.

In pipeline systems there is often a need for devices which can regulatethe fluid flow and likewise there is a need for the mounting of meteringequipment for instance for volumetric metering of fluid flows.

Apparatus of the above-mentioned kind which are placed in a fluid flow,are subjected to considerable wear and tear and demand relativelyfrequent, periodical maintenance. It is desirable that maintenance canbe performed quickly and that it should not be necessary to depressurizethe pipeline. It is also desirable that medium from the pipeline willnot leak out into the surrounding environment when maintenance takesplace.

SUMMARY OF INVENTION

This is achieved by a valve according to the present invention which ischaracterized in that the lower part of the rotatable member ispredominantly U-shaped with sealing surfaces arranged on the outwardlyfacing side-faces, which sealing surfaces are, in the case of a closedvalve, engaged with the valve housing's valve seats on respectively theinlet and/or outlet end, in that the upper part's external surface isdesigned for totally or partly resting support against the lower part'sinternal surface and comprises a through-flow passage (24) intended foraccommodating controlling or metering equipment, in that the upper part,in the case of closed valve, can be withdrawn from the valve housing formaintenance.

BRIEF DESCRIPTION OF DRAWINGS

The invention will be more closely described in the following, makingreference to the accompanying drawings in which:

FIG. 1 shows a vertical section through a valve according to theinvention when the valve is in an open position or an adjustableposition,

FIG. 2 shows a horizontal section through the valve shown in FIG. 1,

FIG. 3 shows a vertical section through the valve as in FIG. 1, but withthe valve in its closed position,

FIG. 4 shows a vertical section through upper part and componentsattached to this, after they have been lifted out of the valve chamberin connection with a maintenance operation,

FIG. 5 shows a horizontal outline of upper part and associatedcomponents which are shown in FIG. 4,

FIG. 6 shows a horizontal outline of the valve housing and lower partafter the upper part has been lifted out,

FIG. 7 shows a horizontal section through the valve housing and lowerpart which keeps the valve closed.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The constructive design of the valve will be described in detail withreference to the FIGS. 1-3. The valve comprises a valve housing 1 with acover 2 which encompasses the upper parts of the valve. The cover issecured to the valve housing by means of locking segments 38. The valvehousing comprises further an inlet flange 3 and an outlet flange 4 whichconnect to a pipeline (not shown) in a known manner. A duct for thefluid flow extends through the valve. In a practical embodiment thereare supporting ribs 37 arranged on the lower side of the valvehousing 1. On the under side of the valve housing 1, an internal bonnet24 is placed between the valve housing 1 and the cover 2.

The rotatable component of the valve includes a U-shaped lower part 6which by way of a journal 7 arranged on a lower side thereof isrotatably mounted in a bearing 8 arranged in a lower part of the valvehousing 1. An upper part 10 is designed to be supportably placed againstthe internal portion of the lower part 6. In order to achieve a firm andstable support between the upper and lower parts, lower part 6 comprisesa rib 5 which engages with a groove 9 (FIG. 5) in upper part 10.

Upper part 10 comprises a through-flow passage 34. In the area of thepassage's 34 respective inlet and outlet, the upper part 10 is providedwith sealing elements 11, 12, which in the shown embodiment are boltedto upper part 10. The sealing elements comprise conical sealing surfaces13, 14 which engage with correspondingly designed valve seats 15, 16 onthe valve housing 1. Lower part 6 comprises correspondingly designedspherical sealing surfaces 17, 18 which, with the rotatable member inthe operating position, as most clearly shown in FIG. 2, faceperpendicularly in relation to the upper part's sealing surfaces 13, 14.The rotating member's turn shaft 25 is pivotally mounted in a checkbearing 23 in the internal bonnet 24. The valve's rotatable member canrotate from an open position as shown in FIG. 1, where the upper part'ssealing faces bear against the valve seats 15, 16, to a closed positionas shown in FIG. 3 where the lower part's sealing faces bear against thevalve seats 15, 16 by rotating the whole rotating member 90°. When thevalve is in a closed position, the lower part stops the fluid flowthrough the valve at both the inlet end and the outlet end.

For rotation of the rotating member, a hydraulic actuator 21 which actson a turn shaft 22 is arranged. The turn shaft 22 is rigidly connectedwith the rotating member's turn shaft 25. The upper portion of the turnshaft 22 comprises splines 25 which engage with the hydraulic actuator21.

Upper part 10 is designed to be able to receive various types ofcontrolling or metering instruments. The object of such equipment canbe:

regulation of flow velocity

recording of flow velocity

measuring of temperature

measuring of pressure

volumetric metering of fluid flow

As an example of such equipment, in the shown embodiment which is mostclearly disclosed in FIG. 3, a controlling mechanism 26 is arranged inthe fluid flow passage 34 for regulation of the fluid flow. In the shownexample, the regulating device 26 comprises rotatable discs 27 which canbe displaced radially in relation to each other in order to close/openthe fluid flow passage 34. In the case of a large drop in pressureacross the valve, two regulating devices 26 can be used as indicated inFIG. 2. Rotation of the rotatable valve discs 27 is executed by means ofa worm gear 28 which is directly connected to a gear ring on at leastone of the valve discs 27. The worm gear is placed in a bore 29 in theupper part 10 and is actuated by a connection motor 30.

For a person skilled in the art it is evident that other equipment, forexample metering or monitoring equipment, can also easily beaccommodated in upper part 10.

With reference to the FIGS. 4-7, a closer description of the method formaintenance of the valve's vital parts and of equipment placed in upperpart 10 will be provided.

The first step will be to close the valve by 90° rotation of therotating member so that the spherical sealing surfaces 17, 18 of thelower part bear against the valve seats 15, 16 of the valve housing 1.The valve will now be closed at both the upstream and downstream ends.

The next step will be to equalize the pressure in the valve room withthe ambient pressure before the cover 2 of the valve housing 1 isdismantled by releasing the locking segments 38. Upper part 10 and theassociated equipment can now be lifted out of the valve housing 1 and beinspected/repaired.

In a preferred embodiment, particularly when used in an underwaterpipeline, upper part 10 and other components which are to undergomaintenance are attached to the underside of the cover 2. All componentscan now be lifted up to the surface via a hook 20 on the outside of thecover. The FIGS. 4 and 5 show the unit which is lifted to the surfacefor maintenance, while the FIGS. 6 and 7 show valve the housing andlower part which remain where they are.

The lower part 6 of the valve can preferably include an automaticlocking mechanism (not shown) which keeps it in a locked position whenupper part 10 is lifted up.

When the upper part with equipment is mounted after overhauling, orpossibly when a new corresponding unit is mounted, the groove 9 mustenter above the rib 5. The unit will halt in a lower position when abearing edge 31 on the overhauled unit encounters the support 32 of thelower part. Bearing surfaces 33 on upper part will fasten the upper partfor sideways position in relation to lower part. Before the cover 2 isfastened in a known way and the valve is rotated into open position, thevalve room should be flushed.

We claim:
 1. A rotatable valve comprising:(A) a valve housing having aninlet and an outlet formed therein and valve seats provided on theinterior of said inlet and said outlet; and (B) a rotatable valvecomponent which is positioned in said housing and which is rotatablefrom an opened position to a closed position, said rotatable valvecomponent including(i) a lower valve part which is generally U-shapedand which has sealing faces formed on external side faces thereof; and(ii) an upper valve part which is insertable into said lower valve partand which is removable for maintenance, said upper part being at leastpartially supported on an internal surface of said lower part, saidupper part having a passage formed therein which can accommodateadditional fluid flow equipment; wherein when said rotatable valvecomponent is rotated to said closed position said sealing faces sealagainst said valve seats and said lower valve part preventscommunication between said inlet and said outlet, and when saidrotatable valve component is rotated to said open position said sealingfaces move away from said valve seats and a said lower part moves toallow communication between said inlet and said outlet via said passage.2. The valve according to claim 1, wherein said upper part has sealingfaces which bear against said seats of said valve housing when saidvalve is in said open position, thereby forming said passage.
 3. Thevalve according to claim 1, wherein said lower part includes a journalwhich is arranged on an underside thereof and which is rotatablysupported on said valve housing via a bearing.
 4. The valve according toclaim 1, wherein said upper part has sealing surfaces comprising sealingmembers having conically shaped sealing surfaces, and wherein said valveseats of said valve housing have shapes corresponding to those of saidsealing members.
 5. The valve according to claim 1, wherein said lowerpart includes a rib which fits into a groove formed in said upper partand maintains said upper and lower parts in fixed positions relative toone another.
 6. The valve according to claim 1, wherein said housingincludes an internal bonnet having a check bearing provided therein, andfurther comprising a hydraulic actuator and a turn shaft which has alower end rigidly connected to said upper part and an upper, free endhaving splines which engage said hydraulic actuator.
 7. A rotatablevalve comprising:(A) a valve housing having an inlet and an outletformed therein and valve seats provided on said inlet and said outlet;and (B) a rotatable valve component which is positioned in said housingand which is rotatable from an opened position to a closed position,said rotatable valve component including(i) a lower valve part which isgenerally U-shaped and which has sealing faces formed on external sidefaces thereof, (ii) an upper valve part which is insertable into saidlower valve part and which is removable for maintenance, said upper partbeing at least partially supported on an internal surface of said lowerpart, said upper valve part having seals which seal against said valveseats when said valve is rotated to its open position and having apassage formed therein which can accommodate additional fluid flowequipment, and (iii) said additional fluid flow equipment including acontrolling device, arranged in said passage of said upper part, forregulating fluid flow through said valve, said controlling deviceincluding rotatable discs which are radially displaceable in relation toeach other;wherein when said rotatable valve component is rotated tosaid closed position said sealing faces seal against said valve seatsand said lower valve part prevents communication between said inlet andsaid outlet, and when said rotatable valve component is rotated to saidopen position said sealing faces move away from said valve seats andsaid lower part moves to allow communication between said inlet and saidoutlet via said passage.
 8. The valve according to claim 7, wherein atleast one of said discs has a gear rim provided thereon, and furthercomprising a worm gear which engages said gear rim.
 9. The valveaccording to claim 8, further comprising a motor which is located in abore formed in said upper part and which drives said worm gear.